In general, in one aspect, in the invention features a first sheet with perforations having a front surface and a back surface and a second sheet with perforation having a front surface and a back surface. Each perforation in the first sheet and the second sheet has a portion adjacent to the front surface of the sheet that is wider than a portion of the perforation that is adjacent to the back surface of the sheet. A core made of a first material is formed between the back surface of the first sheet and the back surface of the second sheet and within the perforations to anchor the first sheet and the second sheet to the core.
Implementations of the invention may also include one or more of the following features. The core may be formed by injection molding, casting or laminating. The first material may include a plastic material, such as a glass filled polycarbonate composite, a resin, epoxy or a cementitious material.
The perforations may be bevelled or counterbored. The first sheet and the second sheet may have perforations in a portion less than the entirety of the sheets.
The support structure may further include a molded feature disposed on the front surface of the first sheet and integrally formed with the core, the molded feature being attached to the core through a perforation in the first sheet.
In general, in another aspect, the invention features a method of assembling a support structure. A first sheet having a front surface and a back surface and perforations therein is provided, with each perforation having a portion adjacent to the front surface of the sheet that is wider than a portion of the perforation that is adjacent to the back surface of the sheet. A second sheet having a front surface and a back surface and perforations therein is provided, each perforation having a portion adjacent to the front surface of the sheet that is wider than a portion of the perforation that is adjacent to the back surface of the sheet. The back surfaces of the first and second sheets are oriented spaced apart from and facing each other. A core is formed between the spaced apart back surfaces of the first and second sheets and in the perforations in the first and second sheets.
Implementations of the invention may also include one or more of the following features. The core may be formed by injecting a first material between the spaced apart back surfaces of the first and second sheets and the first material is hardened. The first material injected between the spaced apart back surfaces of the first and second sheets may flow into the perforations in the first and second sheets. The core may also be formed by casting or laminating.
The orienting step may include placing the first and second sheets into a mold. The method may further include grinding the front surfaces of the first and second sheets.
In general, in another aspect, the invention features a support structure including a first sheet having a front surface, a back surface and a first anchoring member, and a second sheet having a front surface, a back surface and a second anchoring member. A core made of a first material is formed between the back surface of the first sheet and the back surface of the second sheet and anchored to the first anchoring member and the second anchoring member.
Implementations of the invention may also include one or more of the following features. The anchoring members may include perforations in the first sheet and the second sheet, respectively, each perforation having a portion adjacent to the front surface of the sheet that is wider than a portion of the perforation that is adjacent to the back surface of the sheet. The anchoring members may also include studs, expanded metal sheets, or perforated sheets in which the perforations have a portion adjacent to the front surface of the perforated sheet that is wider than a portion of the perforation that is adjacent to the back surface of the perforated sheet.
In general, in another aspect, the invention features a method of assembling a support structure. A first sheet having a back surface and a first anchoring member attached to the back surface, and a second sheet having a back surface and a second anchoring member attached to the back surface, are provided. The back surfaces of the first and second sheets are oriented spaced apart from and facing each other. A core is formed between the spaced apart back surfaces of the first and second sheets.
In general, in another aspect, the invention features a horizontal base. A first sheet with perforations has a front surface and a back surface and a second sheet with perforations has a front surface and a back surface, each perforation in the first sheet and the second sheet having a portion adjacent to the front surface of the sheet that is wider than a portion of the perforation that is adjacent to the back surface of the sheet. A core made of a first material is formed between the back surface of the first sheet and the back surface of the second sheet and within the perforations to anchor the first sheet and the second sheet to the core. A mounting boss is disposed on the front surface of the first sheet and integrally formed with the core, the mounting boss being attached to the core through a perforation in the first sheet.
Implementations of the invention may also include the following feature. The horizontal base may further include a plurality of legs disposed on the front surface of the second sheet and integrally formed with the core, the legs being attached to the core through perforations in the second sheet.
In general, in another aspect, the invention features an end-of-arm tool. A first sheet with perforations has a front surface and a back surface and a second sheet with perforations has a front surface and a back surface, each perforation in the first sheet and the second sheet having a portion adjacent to the front surface of the sheet that is wider than a portion of the perforation that is adjacent to the back surface of the sheet. A core made of a first material is formed between the back surface of the first sheet and the back surface of the second sheet and within the perforations to anchor the first sheet and the second sheet to the core. A plurality of molded features are disposed on the front surface of the first sheet and the front surface of the second sheet and integrally formed with the core, the molded features being attached to the core through perforations in the first sheet and the second sheet.
Implementations of the invention may also include one or more of the following features. The molded features may be bosses or pivot lugs.
An advantage of the present invention is the ease and simplicity of forming the support structure, e.g., a core for an abrasive tool.
Another advantage of the present invention is the strength, durability, and dimensional stability of the support structure, which allows for selection from a wide range of materials.
Another advantage of the present invention is the high strength-to-weight ratios of the composite material used to form the support structure compared to any of the construction materials singularly.
A further advantage is the versatility of the support structure, which may have varying shapes and uses.
Other features and advantages of the invention will become apparent from the following detailed description, and from the claims.